Question

What prevents the backflow of blood inside the heart during contraction?

विकल्प

• Valves in the heart

• Thick muscular walls of ventricles

• Thin walls of atria

• All of the above

Answer 1

Valves in the heart

Explanation - 

The walls of the heart are only responsible for pumping blood; they are not responsible for preventing blood from flowing backwards into the heart during contraction.